Extend JavaScript array to find and remove contained values

ArrayPrototype.js

/*
  Usage example:
  -- array.contains(1)
  Description: Checks if array contains value 1
  Demo: http://jsfiddle.net/Yushell/GTSXh/
*/

Array.prototype.contains = function(obj) {
    var i = this.length;
    while (i--) {
        if (this[i] === obj) {
            return true;
        }
    }
    return false;
}

/*
  Usage example:
  -- array.remove(1)
  Description: Removes the second item from the array  
  -- array.remove(-2)
  Description: Removes the second-to-last item from the array  
  -- array.remove(1,2)
  Description: Removes the second and third items from the array  
  -- array.remove(-2,-1)
  Description: Removes the last and second-to-last items from the array
  Demo: http://jsfiddle.net/Yushell/6VR5P/
*/

Array.prototype.remove = function(from, to) {
    var rest = this.slice((to || from) + 1 || this.length);
    this.length = from < 0 ? this.length + from : from;
    return this.push.apply(this, rest);
};